[145880] in North American Network Operators' Group
Re: Outgoing SMTP Servers
daemon@ATHENA.MIT.EDU (Ricky Beam)
Tue Oct 25 15:32:51 2011
To: nanog@nanog.org
Date: Tue, 25 Oct 2011 15:31:55 -0400
From: "Ricky Beam" <jfbeam@gmail.com>
In-Reply-To: <3576DC1F-8595-42EB-9FC1-74C43B1BAED7@delong.com>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Tue, 25 Oct 2011 12:55:58 -0400, Owen DeLong <owen@delong.com> wrote:
> Wouldn't the right place for that form of rejection to occur be at the
> mail server in question?
In a perfect world, yes. When you find a perfect world, send us an invite.
> I reject lots of residential connections...
The real issue here is *KNOWING* who is residential or not. Only the ISP
knows for sure; and they rarely tell others. The various blocklists are
merely guessing. Using a rDNS name is an even worse guess.
> However, senders who authenticate legitimately or legitimate sources
> of email (and yes, some spam sources too) connect just fine.
Authenticated sources can be traced and shutoff. If a random cablemodem
user has some bot spewing spam, the only way to cut off the spam is to
either (gee) block outbound port 25, or turn their connection off
entirely. As a responsible admin, I'll take the least disruptive path.
(I'll even preemptively do so.)
--Ricky
